- 1). Open the gas cap, a black cap on top of the motor. Look inside to make sure the mower has gas. Fill the tank with regular unleaded gasoline if it is empty.
- 2). Inspect the fuel line and tank for any leaks if you smell gas. Follow the rubber fuel hose as it runs from tank to the carburetor. If there is a hole in the tank, use plastic epoxy to seal it. If there is a hole in the hose, replace it by unscrewing the clamps holding it in place and and attaching a new hose.
- 3). Unscrew the spark plug from the right side of the motor housing with an adjustable wrench. Look for any kind of crack or break on the plug as that could prevent the motor from starting. If there are cracks or breaks, replace the spark plug with a new one, which will cost less than $10.
- 4). Look into the mower's chute for any clogs. If there are or you cannot see inside the deck because it is too dark, turn the mower on its side. Be sure to drain the oil and gas first. Unplug the oil drain plug underneath the deck above the cutting blade and drain the oil into a container. Unscrew the gas cap on top of the mower and tip the open tank into an empty container. Once the motor has been drained, turn it over and look for any chunks of grass that are clogging the arbor around the blade. Iif the blades are blocked, then the motor will not start.
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